Vermes
Advanced Member level 4
It is a design of the lamp for stereo microscope XTL-4. Working with this microscope requires illumination of the observed field, what applies not only to his type of microscope.
Presented construction has an additional advantage – adjustment of current flowing through diodes, and thus the lighting power.
The system is very simple. It is a small transformer with a bridge and filtering capacitor. A well-known LM 317 was applied as the lighting controller (of current flowing through the LEDs). It was used according to its note sheet.
Current is controlled in the range of 20mA – 175mA. For such LEDs system the maximum current is about 225mA, but it was limited to 175mA for the security. With the current LEDs light very intensely. 24 LEDs OSPW5111P with a brightness of 50 000mcd at 75mA were used.
The housing was brought of aluminum. Holes for mounting and grommet for power cord were made. The illuminator can be mounted on the body of the microscope (thread M3).
The last photo shows the microscope with mounted illuminator with a lens 0,5 decreasing magnification, but increasing the field of observation. In this configuration, the illuminator is 16cm above the work table, giving plenty of room to work.
Link to original thread (useful attachment) – Oświetlacz do mikroskopu XTL-4